From the US and Poland, to Hong Kong and Brazil, the Korean pop group's latest album,"Love Yourself: Her," held the top spot on iTunes' top selling album chart in73 countries and territories in three continents.

The music video for the album's debut single, "DNA" hit 20 million views on YouTube in about 20 hours, knocking down records by Taylor Swift, Katy Perry and Rihanna for most views in a day.

The seven member group, whose oldest member is just 24-years-old, is well known for its record breaking firsts. In May 2017, the groupbeat American favorites Justin Bieber, Selena Gomez and Ariana Grande to become the first K-pop act to clinch a Billboard Music Award.

And, for their third world tour this past spring, within hours of going on sale, BTS sold out US arenas — another first for a K-pop act — prompting them to add more shows on both coasts, in New Jersey and California.

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Lately, they've ranked on the 2017 Billboard Year End Charts ((#1 Social 50 Artist, #2 Top Artist Duo/Group, #10 Top Artist and #32 Independent Albums). BTS also performed at the American Music Awards, "The Ellen DeGeneres Show, "The Late Late Show" and will be playing "Dick Clark's New Year's Rockin' Eve in New York.

Kim Nam-joon, known as "Rap Monster," is the leader of BTS.

"We really started at the bottom," said BTS member 23-year-old Kim Namjoon, who writes a lot of the groups songs and as the group's only English speaker, acts as the face of the group outside of Asia. "When we first started no one paid attention to us," added Kim.

Having debuted in 2013, BTS stands for "Beyond The Scene," a reference to their mix of musical styles, including pop, hip-hop, R&B and electronica.

"BTS bucks the trend and does their own thing," said Paul Han, co-founder of Allkpop, a site for K-pop gossip and news, which has 10 million monthly readers worldwide. "If you listen to their past hit songs, it doesn't really sound like they're trying to make a catchy pop song, instead, they're using genuine hip-hop beats with clever wordplay and thought-provoking lyrics."

BTS' newest and fifth album is "all about crossing barriers, language borders and connecting the human experience," said Kim, over the phone from Seoul, South Korea.

"Our songs are about the hardships of young people, their loves and their daily lives."

One of the singles, "Best Of Me," is a collaboration with New York DJ duo The Chainsmokers, whom they met at the Billboard Music Awards.

"They were curious about us," said Kim. "We were of course fans."

This new album expresses a "brighter blast of EDM and softer hip-hop than their past albums" and is "aimed at a wider audience," said Tamar Herman, who covers K-pop for Billboard.com, but she added that it still remains to be seen if that strategy will pay off in the long term.

In the past, Herman said, their success was a mix of work ethic and canny use of technology.

"What sets them apart is definitely their social media," said Herman. "It brings them closer to fans, making them feel as real as idols can get."

For many K-pop fans, particularly those in the US, the internet remains the only way to get access to K-pop content.

"BTS cut out the middle man with their social media posts, bringing instantly shareable content directly to their fan's Twitter feeds," said Herman.

"Paired with their increasingly impressive music releases, BTS gave off a more accessible vibe than many other K-pop acts, whose communication with fans is more often than not directed through limited moments curated by their labels," she added.

This engagement was key to their Billboard win. Their fans, known as the "A.R.M.Y." (Adorable Representative MC's for Youth"), voted for their award on Twitter and on the awards website, using the hashtag #BTSBBMAS more than 300 million times.

"It's become a habit to be natural and always open," said Kim. "We tweet about silly things and every small thing.

"We have seven members, if somebody doesn't use social media that day, the other members do it. We do it every day. It's like brushing teeth."

Allkpop founder Han believes social media is the perfect outlet to showcase a more true to life representation of the group.

"Beyond the music, if you get to know them, you fall in love with their infectious personalities," said Han. "You don't see any fakeness or diva personalities, they all seem genuine, humble, and down to earth."

The seven are in their early 20s, and Kim said, have lived with each other in the same house for the last several years, learning to deal with each other like "brothers."

"We sometimes argue from time to time," said Kim. "We know how to deal with it and how to learn from each other. We have a very special bond."

Kim is the only BTS member fluent in English, having learned it from the "Friends" DVD's his mom gave him.

"The first time I watched it with Korean subtitles, the second with English subtitles and the next time, I managed to watch it with no subtitles, and saw real situations, what Americans deal with," said Kim. "'Friends' helped me so much."

Off this new album, Kim says they are planning another tour. They are also discussing what to do about their upcoming required two-year military service, which has threatened the unity of other K-pop groups before.

And as for what many fans really want to know, Kim said his "ideal girl," would be able to "talk for more than an hour about anything, family, music life, whether we can communicate and have something in common."